• Journal of Electrical Engineering and Technology
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• v.9 no.4
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• pp.1240-1247
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• 2014

The applications of Distributed Generation (DG) in a smart distribution grid environment are widely employed especially for power balancing and supporting demand responses. Using these applications can have both positive and negative impacts on the distribution system. The sizing and location of their installations are the issues that should be taken into consideration to gain the maximum benefit from them when considering the economic aspects. This paper presents an application of the Bat Algorithm (BA) for the optimal sizing and siting of DG in a smart distribution power system in order to maximize the Benefit to Cost Ratio (BCR), subjected to system constraints including real and reactive power generation, line and transformer loading, voltage profile, energy losses, fault level as well as DG operating limits. To demonstrate the effectiveness of the proposed methodology and the impact of considering economic issues on DG placement, a simplify 9-bus radial distribution system of the Provincial Electricity Authority of Thailand (PEA) is selected for the computer simulation to explore the benefit of the optimal DG placement and the performance of the proposed approach.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.7
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• pp.940-945
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• 2018

In this study, we make a study on a system to determine a person's sitting posture by measuring the distribution of pressure in the floor of a chair or in a cushion using pressure sensors. If the wrong sitting posture is detected, a warning message is given through the vibration motor in real time to correct the imbalance of the wrong habits and posture, and prevent Bulging disc or Herniated disc.

• Plant Journal
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• v.7 no.1
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• pp.40-48
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• 2011

This study shows the comparison between expected and actual capacity factors of a wind farm through wind resource analyzation. The expected capacity factor comes from an 'automatic weather system' run by the Korean national weather service and a 'meteorological mast' run by a project owner. Based on this comparison and analysis, the importance of meteorological mast micro-siting and selection of wind turbine class and type, will be studied along with presenting important implications for wind farm expansion and development.

• Journal of Korean Society for Geospatial Information Science
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• v.5 no.1 s.9
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• pp.119-128
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• 1997

With the rapid socioeconomic change the siting of SOC is getting more difficult due to so-called NIMBY syndrome. The objective methodology using GIS was かid as a case study to solve the complexity of the power transmission line routing. We anticipated that the new optimization of transmission routing would be the efficient and reasonable way in getting the public acceptance and settling the public complaints from transmission construction project in our country.

• International Journal of High-Rise Buildings
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• v.12 no.1
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• pp.49-61
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• 2023

The transit-oriented development (TOD) model can effectively help to solve urban problems and promote sustainable urban development. The United States and Japan are widely considered the earliest two countries to start TOD practices; however, the origins of TOD models in the two countries were different. The TOD practices in the two countries formed distinct characteristics, yet their differences have been underexplored. This study aims to grasp the characteristics of the TOD model in the two countries through a systematic comparative analysis of 10 typical cities in the United States and Japan that have adopted the TOD model. This paper compares the case cities' three key aspects of the TOD model: public transit system, spatial form, and land use, and summarizes the characteristics of TOD models in the two countries from a city-level perspective, to help deepen the global understanding of TOD.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.4
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• pp.517-532
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• 2021

Safe geological disposal of spent nuclear fuel (SNF) requires knowledge of the deep hydrochemical characteristics of the repository site. Here, we conducted a set of deep hydrochemical investigations using a 750-m borehole drilled in a model granite system in Wonju, South Korea. A closed investigation system consisting of a double-packer, Waterra pump, flow cell, and water-quality measurement unit was used for in situ water quality measurements and subsequent groundwater sampling. We managed the drilling water labeled with a fluorescein dye using a recycling system that reuses the water discharged from the borehole. We selected the test depths based on the dye concentrations, outflow water quality parameters, borehole logging, and visual inspection of the rock cores. The groundwater pumped up to the surface flowed into the flow cell, where the in situ water quality parameters were measured, and it was then collected for further laboratory measurements. Atmospheric contact was minimized during the entire process. Before hydrochemical measurements and sample collection, pumping was performed to purge the remnant drilling water. This study on a model borehole can serve as a reference for the future development of deep hydrochemical investigation procedures and techniques for siting processes of SNF repositories.

• Journal of the Korea Fashion and Costume Design Association
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• v.6 no.2
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• pp.21-33
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• 2004

The purpose of this study was to provide information on how to improve both the satisfaction and the current sizing system for the school uniform focused on middle and high school girls' students. For the satisfaction of their school uniform, there were statistical significance by the academic year in jacket design, blouse color, and skirt design in the case of middle school girls'. On the other hand, high school girls' evaluation of school uniform was significantly different in jacket color, jacket design, blouse color, textile of blouse, skirt color, and skirt design by the academic year. For the assessment of wearing motion, there was no significant difference by the grade in both middle school and high school girls'. However, it was shown more frequency of discomfort than that of comfort. For the evaluation of sizing fitness, the breadth of sleeve in jacket and the width of blouse were statistical significance in middle school girls' by the grade while the width of jacket, he breadth of sleeve in jacket, the length of blouse, the width of blouse and length of sleeve in blouse were different in high school students by the grade.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.2
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• pp.169-176
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• 1998

Recently, the volume of transportatin is higher by increasing rapid development and human or material interchange among districts. So, the importance of maintenance and management on existing road is come to the fore. In this study, we'd like to build prototypic Road Information Management System to keep road scientifically and efficiently on general road. We built the database of information about a drawing and register on ex-siting road using GSIS. So, we can offer information rapidly and accurately in road maintenance and management service through the query, update and statistic analysis function on road facility as well as AM.

• Nuclear Engineering and Technology
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• v.54 no.4
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• pp.1482-1494
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• 2022

Power conversion cycles (Subcritical Steam, Supercritical Steam, Open Air Brayton, Recuperated Air Brayton, Combined Cycle, Closed Brayton Supercritical CO₂ (sCO₂), and Stirling) are evaluated for land-based nuclear microreactors based on technical maturity, system efficiency, size, cost and maintainability, safety implications, and siting considerations. Based upon these criteria, Air Brayton systems were selected for further evaluation. A brief history of the development and applications of Brayton power systems is given, followed by a description of how these thermal-to-electrical energy conversion systems might be integrated with a nuclear microreactor. Modeling is performed for optimized cycles operating at 3 MW(e) with turbine inlet temperatures of 500 ℃, 650 ℃ and 850 ℃, corresponding to: a) sodium fast, b) molten salt or heat pipe, and c) helium or sodium thermal reactors, coupled with three types of Brayton power conversion units (PCUs): 1) simple open-cycle gas turbine, 2) recuperated open-cycle gas turbine, and 3) recuperated and intercooled open-cycle gas turbine. Aeroderivative turboshaft engines employing the simple Brayton cycle and two industrial gas turbine engines employing recuperated air Brayton cycles are also analyzed. These engines offer mature technology that can facilitate near-term deployment with a modest improvement in efficiency.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.135-141
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• 2008

In this paper a novel tracking system is described, regarding the influence of shadow between array, aimed at improving the efficiency of PV tracking system. Comparing with a building site versus capacity power, domestic solar powers have a limited siting. Therefore, each array interferes with the shadow of other arrays. The loss by influence of those shadow can be compensated for by means of control algorithm of the tracking device. The paper suggests a method controlling an altitude for length which is received the shadow influence of PV array. By using an azimuth of current solar position and the length between arrays, the controller of tracking device is able to calculate the length between actual arrays and make a comparison of the shadow length at a specific time with the length between arrays. When the shadow length is longer than the length between arrays, the controller of tracking device can adjust a position by compensating error altitude of the length between arrays at an altitude of current solar position. In the paper, we develop the control algorithm able to minimize the loss caused by the influence of shadow on the PV tracking system, and compared this with conventional output system. The controller has been tested in the laboratory with proposed algorithm and shows excellent performance